It's wrong to call them characters... but oh well.
Elie: The speaker. He, number A-7713, was one of millions of Jews to be sent to concentration camps. He managed to survive. See the TANG page for info on him personally.
Chlomo: Elie's father. He tried to remain strong for his son, but eventually the starvation and abuse killed him in the final months of the war. His death caused Elie to grow numb and cold, and little after his death was recorded in Night.
Elie's Mother: She was seperated from Elie at the very beginning. She died in Auschwitz.
Tzipora: Elie's little sister. She died in Auschwitz.